Hi Jean,
There were two, William HOLMES that died 1928 in Western Australia. Is "your" man the one who died on 8 Sep 1928?
http://trove.nla.gov.au/ndp/del/article/32221666?searchTerm=... fremantle&searchLimits=l-state=Western+Australia|||l-decade=192|||l-year=1928|||l-month=9|||l-category=Family+Notices
His age, on his burial record matches to a birth of 1876.
First Name: WILLIAM
Last Name: HOLMES
Fremantle Burial
Aged (Years): 52
Date of Death: 08/09/1928
Suburb: FREMANTLE
Now to the marriage certificate. Can you please transcribe all the details, on here?
The witnesses, may be relatives of the married couple.
The names and occupations, of the groom's parents?
His birthplace?
From there, we can check BDM's, if he was born in England, and see if there were other siblings.
Mary